This invention relates generally to irrigation sprinklers of the type having a rotary driven spray head mounted at the upper end of a pop-up riser. More particularly, this invention relates to an improved irrigation sprinkler including an internally mounted debris cup for capturing and retaining debris such as dirt and small pebbles ingested into the sprinkler through the riser, to prevent such ingested debris from contacting and interfering with a rotary drive mechanism.
Pop-up irrigation sprinklers are well known in the art particularly for use in irrigation systems wherein it is necessary or desirable to embed the sprinkler in the ground so that it does not project appreciably above ground level when not is use. In a typical pop-up sprinkler, a tubular riser is mounted within a generally cylindrical upright sprinkler housing or case having an open upper end, with a spray head carrying one or more spray nozzles carried at an upper end of the riser. In a normal inoperative position, the spray head and riser are spring-retracted substantially into the sprinkler case so that they do not extend or project a significant distance above the case or the surrounding ground level. However, when water under pressure is supplied to the sprinkler case, the riser is displaced upwardly to shift the spray head to an elevated spraying position spaced above the sprinkler case. The water under pressure flows through a vertically oriented nozzle passage in the riser to the spray head which includes an appropriately shaped nozzle for projecting a stream of irrigation water generally radially outwardly over a surrounding terrain area and associated vegetation.
In many pop-up sprinkler designs, a rotary drive mechanism is provided within the sprinkler case for rotatably driving the spray head through continuous full circle revolutions, or alternately back and forth within a predetermined part-circle arcuate path, to sweep the projected water stream over a selected target terrain area. In addition, the spray head for the rotary drive pop-up sprinkler is frequently adapted for removable mounting of a selected one of a set of spray nozzle inserts designed to custom-tailor the specific characteristics of the projected water stream, such as flow rate, trajectory range, stream width, and the like, in accordance with the particular irrigation requirements for each pop-up sprinkler. For examples of rotary drive pop-up sprinklers of this general type, see U.S. Pat. Nos. 4,625,914; 4,787,558; and 5,383,600. In addition, such sprinklers are commercially available from Rain Bird Sprinkler Mfg. Corp. of Glendora, Calif. under the product designations T-Bird Series, 3500 Series, R-50, Falcon, and Talon.
It has been recognized that rotary drive sprinklers are susceptible to potential failure upon entry of debris such as dirt and grit or small pebbles into the sprinkler case interior, wherein such ingested debris can contact and jam moving parts of the rotary drive mechanism. To address this problem, such sprinklers have been equipped with inlet filters or filter screens to capture water-borne debris carried by the incoming water supply. In addition, wiper-type seals have been provided to reduce or eliminate debris ingestion along the exterior of the riser as it is displaced between the retracted and elevated spraying positions. However, the spray nozzle and the associated nozzle passage formed in the riser provides an additional pathway for potential debris ingestion into the sprinkler case, particularly when the sprinkler is initially installed in the ground before installing a selected spray nozzle insert onto the spray head. Although such sprinklers are often provided with a plug intended to prevent loose dirt and debris from falling through the nozzle passage into the case interior, occasional ingestion of dirt and small pebbles prior to or during installation of the spray nozzle insert still occurs. If such debris comes into contact with and jams the rotary drive mechanism, such as a water-driven turbine, it is typically necessary to remove the sprinkler from the ground for substantial disassembly and cleaning, or replacement.
There exists, therefore, a need for further improvements in and to the design of rotary drive pop-up sprinklers, particularly with respect to preventing failure of a rotary drive mechanism attributable to ingestion of debris such as dirt and small pebbles entering the sprinkler case through the pop-up riser. The present invention fulfills these needs and provides further related advantages.
In accordance with the invention, an improved pop-up and rotary drive irrigation sprinkler is provided with an internally mounted and upwardly open debris cup for capturing and retaining debris such as dirt and pebbles falling into the sprinkler through a tubular pop-up riser, to prevent such debris from contacting and interfering with an internally mounted rotary drive mechanism.
The sprinkler generally comprises a hollow sprinkler housing or case carrying a pop-up riser with a spray head mounted thereon for projecting a stream of irrigation water to surrounding terrain and vegetation. In a normal inoperative position, the pop-up riser and spray head are retracted substantially into the sprinkler case. During operation, supply of water under pressure to the sprinkler case displaces the riser and spray head thereon to an elevated spraying position, with the spray head spaced above the sprinkler case for facilitated delivery of the water stream to the surrounding terrain. The water under pressure flows through a nozzle passage formed in the riser to the spray head having a nozzle through which the water stream is projected generally radially outwardly. The rotary drive mechanism includes a water-driven element such as a turbine coupled by a reduction gear unit or the like to the spray head for rotatably driving the spray head in a manner sweeping the projected water stream over a selected full-circle or part-circle arcuate pattern.
The debris cup is mounted within the sprinkler case generally at a lower end of the nozzle passage formed in the riser, and in a position generally overlying the water-driven element, to capture and retain debris falling into the sprinkler case through the riser. Accordingly, debris such as dirt and small pebbles which may be ingested into the sprinkler case through the riser, is prevented from contacting and interfering with the water-driven element.
Other features and advantages of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, byway of example, the principles of the invention.